iOS app crashes when going to background if a NetStream is referenced.

Hello there,

this has ben testedby several people on several versions of AIR.

Source code here: https://tracker.adobe.com/api/jira/issue/AIR-4198784/attachment/3439791

On iOS, if a netstream is referenced to a variable, once the app goes to background, then crashes when brought to foreground again. It seems like a null pointer exception on iOS side. Apple console shows a null reference exception.

Just a few lines are enough to cause the bug:

1. private var _ns:NetStream; // This is in class constructor
2. var nc:NetConnection = new NetConnection(); 
3. nc.connect(null); 
4. var ns:NetStream = new NetStream(nc); 
5. /* THIS IS THE CULPRIT. COMMENT "_ns = ns" AND APP WILL NOT CRASH */ 
6. _ns = ns;  // If this is commented, app doesn't crash.

Just bring the app to background, then foreground again, and on iOS it will crash (all works fine on other platforms).

Cheers